If I included the exact same graphics as the original, but I did paint them all by hand myself, would you think that makes a difference? No it doesn’t. And what you are proposing is just the same with extra steps. They could include graphics that don’t look the same but I guess that defeats the reason for the game.
There’s a middle ground. For instance OpenTTD has fan made artwork that matches the aesthetic of the original game without being a direct copy. Still plenty of reason to play even if it doesn’t look exactly like it does in my memories.
For me the game is mostly about the mechanics and I don't think I'd have any issue playing it with an entirely different visual and auditory design, assuming it can be made to be self-consistent.
